1.
[tex]dane:\\s = 830 \ m\\F = 43 \ N\\szukane:\\W = ?\\\\W = F\cdot s\\\\W = 43 \ N\cdot830 \ m\\\\W = 35 \ 690 \ J = 35,69 \ kJ[/tex]
2.
[tex]dane:\\P = 987 \ W\\t = 1 \ min = 60 \ s\\szukane:\\W = ?\\\\P = \frac{W}{t} \ \ /\cdot t\\\\W = P\cdot t\\\\W = 987 \ W\cdot60 \ s\\\\W = 59 \ 220 \ J = 59,22 \ kJ[/tex]
3.
[tex]dane:\\m = 1,5 \ kg\\h = 4,5 \ m\\g = 10\frac{N}{kg}\\szukane:\\E_{p} = ?\\\\E_{p} = mgh\\\\E_{p} = 1,5 \ kg\cdot10\frac{N}{kg}\cdot4,5 \ m\\\\E_{p} = 67,5 \ J[/tex]
4.
[tex]dane:\\m = 3,5 \ kg\\v = 18\frac{m}{s}\\szukane:\\E_{k} = ?\\\\E_{k} = \frac{1}{2}mv^{2}\\\\E_{k} = \frac{1}{2}\cdot3,5 \ kg\cdot(18\frac{m}{s})^{2}}\\\\E_{k} = 5657 \ J[/tex]
